Calculation of forces coefficients

aja1345 · October 28, 2015, 18:28

Hi,

I studied a thesis about a axial turbine and but i didn't understood the bold part of following sentences. What is the exact meaning of "dot product of the pressure and viscous force coefficients on each face with the specified force vector"? This thesis is performed by using Fluent.

*The forces coefficients (CA and CT) on blade surface were calculated by summing the dot product of the pressure and viscous force coefficients on each face with the specified force vector.

I am grateful that guide me about this.
Thanks.

Best.

LuckyTran · October 29, 2015, 00:06

The total force is a sum of the forces due to pressure and viscous drag. So you must take the dot product of the pressure force and the direction vector and then separately the dot product of viscous drag force and direction vector. It is not taking the dot product of the pressure force and viscous force.

aja1345 · October 29, 2015, 12:46

Quote:

Originally Posted by LuckyTran

The total force is a sum of the forces due to pressure and viscous drag. So you must take the dot product of the pressure force and the direction vector and then separately the dot product of viscous drag force and direction vector. It is not taking the dot product of the pressure force and viscous force.

Thanks.

How do i compute these cases in Ansys Fluent?

I am grateful that guide me more.

Thanks.

Best.

Aja

October 28, 2015, 18:28	Calculation of forces coefficients	#1
aja1345 Senior Member Aja Join Date: Nov 2013 Posts: 496 Rep Power: 15	Hi, I studied a thesis about a axial turbine and but i didn't understood the bold part of following sentences. What is the exact meaning of "dot product of the pressure and viscous force coefficients on each face with the specified force vector"? This thesis is performed by using Fluent. The forces coefficients (CA and CT) on blade surface were calculated by summing the dot product of the pressure and viscous force coefficients on each face with the specified force vector.* I am grateful that guide me about this. Thanks. Best.

October 29, 2015, 00:06		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,752 Rep Power: 66	The total force is a sum of the forces due to pressure and viscous drag. So you must take the dot product of the pressure force and the direction vector and then separately the dot product of viscous drag force and direction vector. It is not taking the dot product of the pressure force and viscous force. aja1345 likes this.

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